Hello, fellow Monks!

Please enlighten me on what's going on with the use of my combined with an if statement modifier on the 4th line. The output is very surprising. I expected the output to be "1\n2\n".

The value of @a is being retained between invocations of fn(). But if the stack frame for fn() is destroyed between calls, where is the value of @a being kept? If my is not having the effect of creating a local due to the if, then why doesn't the compiler complain that @a is an undeclared global? 

perl -we '
  use strict;
  sub fn {
    my @a = (7) if 0;
    push @a, @_;
    print "@a\n";
  }
  fn 1;
  fn 2;
'
1
1 2

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In reply to Curious result of using "my ... if ..." by jrw

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